Belostomatidae are fierce predators which stalk, capture and feed on aquatic crustaceans, fish and amphibians. They have also been found to capture and feed on baby turtles and water snakes.[1] They often lie motionless at the bottom of a body of water, attached to various objects, where they wait for prey to come near. They then strike, injecting a powerful digestive saliva with their rostrum, and sucking out the liquefied remains. Their bite is considered one of the most painful that can be inflicted by any insect Occasionally when encountered by a larger predator, such as a human, they have been known to "play dead" and emit a fluid from their anus.[2] Due to this they are assumed dead by humans only to later "come alive" with painful results.[2]

Was trying to catch grass shrimp for bait once, reached into the net blindly to remove contents, jerked hand out, screamed like ten year old girl, threw contents down inside the boat, threw net halfway across canal never to be recovered. Hurt like hell. Wish I had video.

ETA: in reading the bite description, I'm not sure it was the same bug. There was no lingering sting or infection, just intense pain at the moment.